Check valves are utilized for hydraulic fluid flow in vehicle drivetrain couplings such as disclosed by U.S. Pat. Nos. 5,310,388 Okcuoglu et al., 5,536,215 Shaffer et al., and 5,595,214 Shaffer et al., the entire disclosures of which are hereby incorporated by reference. One consideration with check valves is that the fluid flow that can pass through the valve in its open position is limited by the valve element since the fluid must flow around the valve element and the valve bore in which the valve element is located cannot be too large to increase fluid flow or there will not be proper guiding of the valve element in its movement to the closed position.
U.S. Pat. No. 4,428,464 Miura discloses a hydraulic damper having a valve that includes a generally flat valve element that is movable within a valve guide that has indentations for providing guiding movement during movement between open and closed positions. Other check valves are disclosed by U.S. Pat. Nos.: 3,219,057 Knowles; 3,343,564 Peeples et al.; 3,880,130 Hecht; 4,091,839 Donner; 4,365,648 Grothe; 4,700,741 Murphy; and 5,183,075 Stein.